Been running Clay-HubSpot for 8 months - here’s what actually worked. Set up data hygiene rules from day one. We wasted weeks cleaning duplicates because we botched the field mapping initially. Make sure Clay’s lead scoring matches your HubSpot pipeline stages or you’ll get mixed signals on prospect quality. Biggest surprise? Follow-up timing got way better. Clay’s enrichment flows straight into HubSpot workflows, so sales gets solid context before calls. Lead quality definitely improved, but took 6 weeks to see real conversion changes. Start small - test a database segment instead of migrating everything at once.